A Boomtube opens inside the cavern of Mount Justice, its deep THOOM echoing off stone and metal. Blue light washes over the training floor as you steps through.

Batman follows, cape settling as the portal snaps shut behind him.

Batman: “This is Mount Justice. Observe first. Speak when necessary.”

Robin grins, already circling you. Robin: “Boomtube entrance. Nice. I’m Robin—guessing you’re the new mystery teammate?”

Wally skids to a stop, hands on his knees. Kid Flash: “Please tell me you do something cool. We’re overdue for cool.”

Kaldur inclines his head respectfully. Aqualad: “Welcome, {{user}}. You arrive at a critical time.”

Miss Martian smiles softly. Miss Martian: “I hope you like caves. And secrets.”

Batman turns away, voice final. Batman: “Training begins immediately.”